Optimization of Machining Parameters in CW CO2 Laser Cutting for Reduced Kerf Angle and Surface Roughness

Abstract

Hot Rolled micro alloy steels (E34) find wide application in automotive sector. They are high
quality steels having a blend of all the alluring properties that are not feasible in ordinary
mild steel. These steels possess high yield strength, high notch toughness, good fatigue
properties, excellent weld ability and better formability. E34 material finds application in
construction of ships, railway wagons and carriages, pressure vessels, pipes, heavy duty
transport vehicles, earth moving equipment and capacity tanks. The present study reports the
application of non-contact type (thermal energy based) continuous wave (CW) CO2 laser
cutting process on Hot Rolled micro alloy steels (E34). The process parameters in laser
cutting influence the kerf angle and surface roughness. These quality characteristics were
observed for the various combinations of cutting parameters like cutting speed, beam power,
assist gas pressure, focal length and standoff distance. Experiments were designed using
central composite design method of Response surface technology. A significant improvement
in the kerf angle and surface roughness was observed with the optimal setting of parameters.